of Mr. George Bishop of the Regent's Park. Here, besides calculating the orbits and declinations of a great number of planets and comets, he was early intrusted by Mr. Bishop with the formation of a set of charts of the heavens, extending to three degrees on each side of the ecliptic, and embracing all stars down to those of the eleventh magnitude. During the careful observation of the heavens required in the compilation of this work, Mr. Hind made a series of discoveries which have rendered his name famous. His first discovery was that of a comet on the 29th of July, 1846; it was afterwards ascertained, however, that the same comet had been seen three hours earlier by De Vico at Rome. On the morning of October 19 of the same year, he discovered another comet in the constellation Coma Berenices; and on February 6, 1847, another. The following planets—all between the orbits of Mars and Jupiter, and forming according to a favourite theory, fragments of what was once one large planet—were discovered by him in rapid succession—Iris, discovered August 13, 1847; Flora, October 18, 1847; Victoria, September 13, 1850; Irene, May 19, 1851; Melpomene, June 24, 1852; Fortuna, August 22, 1852; Calliope, November 16, 1852; Thalia, December 15, 1852; Euterpe, November 8, 1853; Urania, July 22, 1854. In his searches for small planets Mr. Hind detected a considerable number of variable stars, or stars which shine at different times with different degrees of brilliancy. In 1851 Mr. Hind, accompanied by the Rev. W. R. Dawes, went to Rævelsberg in Sweden to observe the total eclipse of the sun, which took place on the 28th of July of that year. The narrative of this expedition was published in the Transactions of the Royal Astronomical Society. From 1853 Mr. Hind was employed by the lords of the admiralty in superintending the compilation of the Nautical Almanac Mr. Hind's labours in the advancement of astronomy have not been unappreciated. In 1844 he was chosen fellow of the Royal Astronomical Society, in 1846 and 1847 foreign secretary and corresponding member of the Société Philomathique of Paris, and in 1851 corresponding member of the Académie des Sciences of the Institute of France. He received medals and testimonials from the Royal Society, the Royal Astronomical Society, and the Académie des Sciences, and in 1852 a pension of £200 per annum from the British government was awarded to him "for important astronomical discoveries." The most important of his works are undoubtedly the papers relating to his own discoveries and observations, which have appeared in the Transactions of the Royal Astronomical Society, and the Comptes Rendus of the Académie des Sciences. But besides these he published several volumes of a popular cast, which have done good service to the study of astronomy. He died in 1866.—E. A. R.
HINGHAM or HENGHAM, Sir Ralph de, a distinguished name in the early legal history of England, flourished during the reign of Edward I. Concurrently with a canonry in St. Paul's, Hingham held the appointment of a justice of the king's bench, and on the institution of justices in eyre, the king made him one of the new dignitaries. During his visit to the Holy Land the king named Hingham chief commissioner for the government; but on Edward's return he was convicted of corrupt practices, dismissed from his preferments, and banished. On the accession of Edward II. he was restored to favour, and made chief justice of the common pleas in 1308, but he died in the same year, and was buried in St. Paul's. His only work, "Summa Magna et Parva," has been often printed.—W. C. H.
HIPPARCHUS. See Pisistratus.
HIPPARCHUS (Ἱππαρχος), the greatest astronomer of ancient times, and one of the greatest astronomers and mathematicians of all times, flourished from 160 to 125 b.c. He was born either in Bithynia or in the island of Rhodes, where his astronomical observations were made. An unimportant fragment of his writings having alone survived, our knowledge of his discoveries is derived from the statements of other writers, especially Ptolemy and Pliny. He invented trigonometry, both plane and spherical, and so made a step in the progress of mathematics to which only three others can be compared—the invention of algebra, that of the Cartesian geometry, and that of the differential and integral calculus. In connection with his invention of trigonometry were that of tables of chords for facilitating trigonometrical calculations, that of the stereographic projection of the sphere, that of defining the positions of places on the earth's surface by latitude and longitude, and the directions of the heavenly bodies, and that of the astrolabe. He discovered the inequality of the apparent motions of the sun and moon, and the eccentricity of the moon's orbit; and he calculated ephemerides, or tables of the apparent positions of those bodies, which, according to Pliny, extended to six hundred years in advance. He determined the parallax of the moon, and made a good approximation to her distance from the earth. The appearance of a temporary star induced him to make a catalogue of the fixed stars, the first ever compiled. The most remarkable of his astronomical discoveries was that of the precession of the equinoxes, a motion by which the pole of the earth's axis shifts its apparent direction amongst the stars; and he came so near the exact annual rate of that motion as to state that it was greater than thirty-six seconds, its true rate having since been found to be about fifty seconds. If the discoveries of Hipparchus be considered with reference to the general state of scientific knowledge in his time, he deserves to be honoured as the founder of the exact sciences of geography and astronomy, and as a genius of the same order with Archimedes and Newton.—W. J. M. R.
HIPPEL, Theodor Gottlieb von, was born at Gerdauen in Prussia Proper, 31st January, 1741, and studied law at Königsberg. He was successively raised to several high positions. His character was a curious composition of piety and worldliness, of virtuous enthusiasm, egotism, and sensuality. He never married; yet his most celebrated works were those on marriage and on the political improvement of women! The rest of his writings have been consigned to oblivion. He died at Königsberg in 1796.—K. E.
HIPPIAS. See Pisistratus.
HIPPOCRATES, the name of several ancient physicians, who probably all belonged to the same family, that of the Asclepiadæ, and who have been so confounded together, that it is impossible to state with certainty either how many persons of this name can be distinguished, or the details of the life of each individual. It will be sufficient in this place to notice only the most eminent of these physicians:—Hippocrates II., the son of Heraclides, who is frequently called by the honourable title of the "Father of Medicine," and who is, perhaps, the most celebrated medical writer of ancient or modern times. Of his personal history very few particulars are known. He was born, not in Greece proper, but in Cos, a small island off the coast of Caria, probably 460 b.c. He accordingly lived in the age of Pericles, and was the contemporary of Herodotus, Thucydides, Socrates, Plato, Democritus, and others of the most celebrated characters of antiquity. He was descended from Æsculapius by his father's side, and from Hercules by his mother's; was instructed in medical science by his father; travelled in different parts of the continent of Greece; and died at Larissa in Thessaly, at a good old age, probably 357 b.c. His two sons, Thessalus and Draco, and his son-in-law, Polybus, were also eminent physicians, and are supposed to have been the authors of some of the treatises that bear his name. Such are the few and scanty facts that are known of the personal history of this celebrated man; but, though we have not the means of writing a detailed biography, we possess in these few facts, and in the hints and allusions contained in various ancient authors, sufficient data to enable us to appreciate the part he played, and the place he held among his contemporaries. We find that he enjoyed their esteem as a practitioner, a writer, and a professor; that he conferred on the ancient and illustrious family to which he belonged, more honour than he derived from it; that he rendered the medical school of Cos, to which he was attached, superior to any which had preceded it or immediately followed it; and that, soon after their publication, his works were studied and quoted by Plato.—(See Littrés Hippocr. vol. i., and a review of that work, by the present writer, in the Brit. and For. Med. Rev., vol. xvii. p. 459.)
Besides these few facts, which may be considered tolerably trustworthy, various stories relating to Hippocrates are to be found in the later Greek, Arabic, and mediæval writers, which may be just alluded to in this place, but may safely be rejected as spurious. Such are—1. His discovering, by certain external symptoms, that the sickness of Perdiccas II., king of Macedonia, was occasioned by his having fallen in love with his father's concubine; 2. His having checked the plague at Athens, in the Peloponnesian war, by burning fires throughout the city, and other modes of purifying the air; 3. His refusal to go to Artaxerxes Longimanus, king of Persia, during a time of pestilence, on the ground of his being the enemy of his country;
